水蒸气辐射特性分析与计算

Analysis and Calculation of Radiative Properties of Water Vapor

利用宽带k分布的传统模型和改进模型计算了水蒸气主要辐射带的吸收系数k与累积分布函数g(k)的对应关系,并与逐线计算结果进行对比,对于工程应用较为重要的大吸收系数范围,宽带k分布的改进模型计算结果与逐线计算更为接近;利用指数宽谱带模型、宽带k分布模型的传统模型与改进模型计算了水蒸气各谱带在不同温度、不同行程长度下的发射率,通过与逐线计算结果比较,宽带k分布的改进模型的误差相对较小,并且该模型计算简单,更适合常压下水蒸气辐射特性计算。

Two wide-band correlated-k distribution models,improved wide-band correlated-k distribution model and traditional wide-band correlated-k distribution model,were used to calculate the absorption coefficient cumulative distribution function of water vapor.The results were compared with results of line by line calculations.The results show that the improved model accurately describes the absorption coefficient distributions compared to existing line-by-line results.The emissivity of carbon dioxide under different temperatures and range of path lengths were obtained.It is concluded that the improved wide-band correlated-k distribution model are more close to the benchmark results.The improved model yields more accurate results of water vapor.